The inventive concept relates to a memory controller, and more particularly, to a control method of a memory controller.
Semiconductor memory devices may be classified into volatile memory devices, which lose stored data when power is not supplied thereto, and non-volatile memory devices, which do not lose stored data when power is not supplied thereto. The volatile memory devices have high read and write speeds, but when external power is not supplied thereto, content stored therein disappears. On the contrary, the non-volatile memory devices have lower read and write speeds than the volatile memory devices, but even when external power is not supplied thereto, content stored therein is maintained.
For example, in a non-volatile memory device such as a flash memory device, as the number of bits of data stored in one memory cell increases, a threshold voltage distribution of memory cells included in the memory device may need to be formed more elaborately. A read error may occur when the threshold voltage distribution is formed more widely than a predicted threshold voltage distribution or formed at a location after parallel translation. Methods of performing a highly reliable data read operation when a threshold voltage distribution of memory cells is changed may be needed.